Maintainer	Anders Claesson <anders.claesson@gmail.com>
Safe Haskell	None

Math.Sym.Class

Description

A permutation class is a downset in the poset of permutations ordered by containment. This module provides definitions of some common classes.

Synopsis

Documentation

inc :: Perm a => Int -> [a]Source

The class of increasing permutations.

dec :: Perm a => Int -> [a]Source

The class of decreasing permutations.

Av(123).

Av(132).

Av(213).

Av(231); also know as the stack sortable permutations.

Av(312).

Av(321).

vee :: Perm a => Int -> [a]Source

The V-class is Av(132, 231). It is so named because the diagram of a typical permutation in this class is shaped like a V.

The ∧-class is Av(213, 312). It is so named because the diagram of a typical permutation in this class is shaped like a ∧.

gt :: Perm a => Int -> [a]Source

The >-class is Av(132, 312). It is so named because the diagram of a typical permutation in this class is shaped like a >.

lt :: Perm a => Int -> [a]Source

The <-class is Av(213, 231). It is so named because the diagram of a typical permutation in this class is shaped like a <.

The union of vee, caret, gt and lt.

The class of separable permutations; it is identical to Av(2413,3142).